feat(settings): add feature gates functionality for the first time IQ…

…SS#9229 IQSS#7000

src/main/java/edu/harvard/iq/dataverse/settings/FeatureGates.java

@@ -0,0 +1,40 @@
+package edu.harvard.iq.dataverse.settings;
+
+/**
+ * <p>This enum holds so-called "feature gates" aka "feature flags". It can be used throughout the application
+ * to avoid activating or using experimental functionality or feature previews that are opt-in.</p>
+ *
+ * <p>The current implementation reuses {@link JvmSettings} to interpret any
+ * <a href="https://download.eclipse.org/microprofile/microprofile-config-3.0/microprofile-config-spec-3.0.html#_built_in_converters">boolean values</a>
+ * (true == case-insensitive one of "true", "1", "YES", "Y", "ON") and hook into the usual settings system
+ * (any MicroProfile Config Source available).</p>
+ *
+ * If you add any new gates, please add a setting in JvmSettings, think of a default status, add some Javadocs
+ * about the gated feature and add a "@since" tag to make it easier to identify when a gate has been introduced.
+ *
+ */
+public enum FeatureGates {
+
+    /**
+     * Enabling will unblock access to the API with an OIDC access token in addition to other available methods.
+     * @apiNote Open gate by setting "dataverse.feature.api-oidc-access"
+     * @since Dataverse 5.13
+     * @see JvmSettings#GATE_API_OIDC_ACCESS
+     */
+    API_OIDC_ACCESS(JvmSettings.GATE_API_OIDC_ACCESS, false),
+
+    ;
+
+    final JvmSettings setting;
+    final boolean defaultStatus;
+
+    FeatureGates(JvmSettings setting, boolean defaultStatus) {
+        this.setting = setting;
+        this.defaultStatus = defaultStatus;
+    }
+
+    public boolean enabled() {
+        return setting.lookupOptional(Boolean.class).orElse(defaultStatus);
+    }
+
+}

src/main/java/edu/harvard/iq/dataverse/settings/JvmSettings.java

@@ -46,6 +46,10 @@ public enum JvmSettings {
     SCOPE_API(PREFIX, "api"),
     API_SIGNING_SECRET(SCOPE_API, "signing-secret"),
 
+    // FEATURE GATES SETTINGS
+    SCOPE_GATES(PREFIX, "feature"),
+    GATE_API_OIDC_ACCESS(SCOPE_GATES, "api-oidc-access"),
+
     ;
 
     private static final String SCOPE_SEPARATOR = ".";